Some known harvesting equipment employ harvesting headers to cut crops for various purposes, such as for windrowing or swathing, or for the feeding of a combine harvester.
Attached to the front portion of a combine harvester or other equipment such as for example a swather) is the portion referred to as the header. A typical header is equipped with a crop cutting mechanism (often referred to as a cutter bar), and a conveyor deck or surface behind the cutter bar onto which cut crop material will fall for direction to a windrow discharge or into the combine. The header also typically includes a bat reel, which is typically a reel mounted between two rotational mounts at either end of the header with a rotational power drive attached thereto, with rotating bats that gather standing crop material into the cutter bar and transfer the cut crop onto a draper table.
With headers of increasing width, there are a number of manufacturing parameters or limitations with respect to the header frame which limit the ability to extend the length (or harvesting width) of the header. One limitation is the weight and complexity of the mechanical power system used to actuate the cutting mechanism such as a cutting knife, as the width of the header increases.
In known headers, a cutting knife is typically driven by either a hydraulic or mechanical drive. The drive mechanism translates power derived from a central location of the harvesting header to an outer end of the harvesting header, where reciprocating motion may be applied, to cause the cutting knife to move back and forth in its guide and cut crop material that comes into contact or close proximity with the cutting mechanism. An issue with such an approach is that, whether hydraulics or mechanical power are used to drive the cutting knife, the addition of a reciprocating drive mechanism at the outer end of the harvesting header results in the addition of significant outboard weight to the header, causing balance issues. Additionally, by providing the necessary components to these drives add significant weight to the header as well. Finding a way to minimize the weight of cutting knife drive components in a harvesting header is desirable.
Translating rotational power from the combine or other power unit, or even providing hydraulic power, to a knife drive assembly located at one or both ends of header table, results in significant mechanical complexity during construction and maintenance of the knife drive mechanism. In addition to the relatively large number of parts typically involved in the construction and maintenance of known harvesting headers, it can be difficult to perform in-field service on this type of the knife drive assembly. A way to drive the cutting knife of harvesting headers which minimized or at least reduced the number of parts, for repair purposes or otherwise, would be desirable in the industry as a means of streamlining repair and maximizing or at least increasing harvesting header uptime in the field.
Another issue with known knife drives used in known harvesting headers is that of vibration during operation of the harvesting header. Particularly, in a harvesting header knife drive that drives the cutting knife along the entire width of the harvesting header from a single drive point/location at one end of the harvesting header, there can be significant vibration of the harvesting header and the entire combine harvesting unit as the knife operates. Even in known knife drives that are centrally located near the center line of the harvesting header, vibration has been an issue. A way to minimize, or least reduce, the amount of vibration of the header, and that would maximize or increase the efficiency of the unit, as well as the level of operator comfort, is desirable.
Another limitation associated with known harvesting headers is the interruption, or interference, with an otherwise streamlined or low profile at the cutter bar on the harvesting header. The interruption or interference impedes the efficacy of the harvesting header overall and can interfere with crop flow. Typical central drive solutions for cutting knives in a harvesting header are typically either flush on the bottom of the cutter bar with the drive components protruding on top, or are flush to the top of the cutter bar with drive components protruding out the bottom. Any non-conformity or significant height difference in the area of the draper deck and the cutting bar acts as a barrier to crop flow. A knife drive for use with a harvesting header having a sufficiently low profile at the cutter bar to allow for normal or low skid plate profiles under the cutter bar would allow for the cutting knife to be positioned as low as possible to perform near the ground.
Additionally, some known center cutting knife drives utilize a gearbox that is quite wide and deep, resulting in a negative impact on crop flow and performance, and limit additional cutter bar features. For example, some known harvesting headers often include rock traps and other features. The ability to include such features near the cutter bar on a harvesting header where a conventional center cutting knife drive is used is limited, due to the space consumed by the drive components.